How do success rates and patient satisfaction compare between VEDs, oral PDE5 inhibitors, and intracavernosal injections?
Executive summary
Oral PDE5 inhibitors are the first-line treatment for ED with typical efficacy around 60–70% in on‑demand regimens and generally high patient satisfaction when they work [1]. Intracavernosal injections (ICI/alprostadil/Trimix) produce erections in roughly 60–90% of men in published series and trial data report per‑injection satisfaction rates as high as 86–87% [2] [3]. Vacuum erectile devices (VEDs) have limited high‑quality efficacy data for refractory ED and evidence is mixed; recent systematic review notes available evidence is limited though VEDs remain recommended in some guidance [4].
1. Oral PDE5 inhibitors: the default first line — proven, preferred, but not universal
PDE5 inhibitors (sildenafil, tadalafil, vardenafil, avanafil) are the standard first‑line medical therapy. Systematic reviews and clinical pharmacology reviews report that oral PDE5‑Is are superior to placebo and produce clinically meaningful erections in roughly 60–70% of men treated on demand; counselling and dose/agent switching can convert some non‑responders [5] [1]. Patient‑preference studies show no clear “best” PDE5 agent — choice is individualized based on onset, duration, side‑effect profile and cost — and satisfaction improves with partner involvement and time after events like prostatectomy [6] [7] [8]. Limitations: up to 30–40% fail to respond to PDE5‑Is alone, and efficacy depends on intact nitric‑oxide signalling and correct use (timing, food effects) [8] [1].
2. Intracavernosal injections: highest efficacy, but adherence and invasiveness matter
ICI therapies deliver vasoactive drugs directly into the corpora and consistently show high efficacy. Meta‑analyses and case series report pooled success estimates around 80–90% for achieving satisfactory erections in many cohorts; classic randomized and observational data show per‑injection satisfaction as high as 86–87% and overall success rates of 60–80% depending on formulation and population [2] [3] [9]. Several large program reviews and long‑term studies stress that ICI yields very high success even in men with comorbidities and PDE5 non‑responders [10] [11]. Downsides: real‑world discontinuation/dropout is substantial (reported 20–50% within the first year in older series, and long‑term continuation often falls to 40–65%), side effects include penile pain, priapism and fibrosis risk with prolonged use [12] [13] [14] [15]. Context: ICI is typically second‑line after oral failure; many patients stop because of invasiveness or spontaneity concerns even when efficacy is high [13].
3. Vacuum erectile devices: under‑studied but useful in select settings
VEDs create erections mechanically and have guideline support for penile rehabilitation and as a non‑pharmacologic option, but recent systematic review highlights limited, lower‑quality evidence for efficacy in refractory ED populations [4]. The 2025 meta‑analysis explicitly states evidence on VED efficacy in PDE5‑refractory ED is limited, though international panels still offer recommendations on their use [4]. Practical advantages: non‑invasive, no systemic drug interactions; drawbacks: device discomfort, clamping rings needed for maintenance of rigidity, and variable patient acceptance. Available sources do not provide robust head‑to‑head success‑rate comparisons of VEDs versus PDE5‑Is or ICI [4].
4. How patients experience these options: satisfaction, spontaneity and tradeoffs
Patient satisfaction tracks both effectiveness and convenience. When oral PDE5‑Is work, they offer spontaneity and favorable tolerability that drive uptake and satisfaction [7] [16]. ICI yields the highest per‑use effectiveness and high satisfaction scores among continuing users, but the need to self‑inject, penile pain and dropout reduce long‑term adherence [3] [15]. VEDs are non‑invasive and avoid medication side effects but face patient acceptance barriers and limited robust efficacy data in refractory cases [4]. Severity of ED predicts lower satisfaction with PDE5‑Is and more likely use of second‑line therapies [17].
5. Putting numbers side‑by‑side and reading the caveats
- Oral PDE5‑Is: efficacy about 60–70% with on‑demand regimens; many studies and meta‑analyses report superiority vs placebo and no clear single best agent [1] [5] [6].
- ICI/alprostadil/Trimix: success ranges widely across studies — commonly reported 60–90% for producing erections; pooled estimates around 80–90% in non‑RCT series and per‑injection satisfaction ~86–87% in trial reports [2] [3] [9].
- VEDs: evidence limited for refractory ED; systematic review characterizes VED efficacy evidence as limited despite guideline recommendations [4].
These comparisons come from different study designs, populations (post‑prostatectomy, diabetic, spinal cord injury), and endpoints (per‑injection satisfaction vs patient‑level responder rates), so direct numerical comparisons are imperfect [1] [2].
6. Bottom line for patients and clinicians
Start with shared decision making: offer PDE5‑Is first because of proven population efficacy (60–70%), ease and satisfaction when effective [1] [5]. For true non‑responders or nitrate‑treated patients, ICI provides the highest on‑demand success rates and high per‑use satisfaction but carries invasive‑use and adherence challenges [2] [3] [15]. VEDs remain an option when drugs are contraindicated or unwanted, but high‑quality evidence in refractory patients is limited [4]. Clinical choice should weigh efficacy, safety, spontaneity, costs and patient/partner preferences [16] [18].